Today, silicon photodiodes for short range applications such as board-to-board and inter-chip optical communications are receiving much attention due to their low cost and capability to integrate with CMOS circuitry. Since the state-of-the-art technology provides shallow n-well depth around 1 μm or less and the absorption depth of 850 nm light in silicon is about 28 μm, the electrons generated in the substrate have to slowly diffuse a long distance to reach the depletion region to be collected as a photocurrent. Consequently, this substrate diffusion current component limits the bandwidth of the silicon photodiode. In order to boost the bandwidth of the silicon photodiode, prior art systems have applied differential or spatially modulated techniques to eliminate the slow substrate diffusion current. Other prior art approaches to enhance the bandwidth include modifying the applied reverse voltage or structure of the photodiode. However, these techniques have drawbacks, such as reduced responsivity. Therefore, improvements are needed in the field.